Cranberry Upside Down Cake

This is Alice Water's recipe that I got from the blog Lottie + Doof. I first had this at my friend, Rachel's house and have been wanting to make it ever since. The beauty of this dish is that you can make it in a cast iron skillet. It's also really easy to make adjustments to this cake, say, to make it gluten free.
This post will be about the Tet holiday (or the Lunar New Year) in Vietnam. We got a 2 week break from work to spend with my family. This is the time when you go home to visit your family if you live far away. A good chunk of the population of Saigon is from the countryside. It's a calmer time for the city since pretty much all the shops are closed. Tet lasts for 5 days officially and during this time, people are going in and out of each other's houses to visit and best of all, eat. We've been eating so much these last few weeks. I've met so many cousins that I didn't even know I had. There's an incredible sense of community here that is refreshing. So many people have invited us into their homes and shared food with us. I would say about 100+ people have come to my grandparent's house to wish them good health and bring them gifts. By the way, they market oreos and ritz crackers as luxury goods here so those were some gifts that I ate. We handed out lucky money in red envelopes to the little kiddies. They have to wish us a happy and prosperous year before they get the dollars though.
The last 3 days, we got to spend at the beach in my dad's old hometown (Mui Ne). It's a beautiful fishing village that is filled with Russian tourists. We stayed at a resort with some cousins and friends and had a blast. Lots of seafood, sunshine, and playing with my little cousins. Now, back to the recipe!

1 1/2 sticks (12 tablespoons) unsalted butter, divided
3/4 cup brown sugar
2 3/4 cups fresh cranberries
1/4 cup apple cider
2 eggs, at room temperature, separated
1/2 cup almond milk
1 1/2 cups unbleached all-purpose flour
2 teaspoons baking powder
1/4 teaspoon salt
1 cup brown sugar
1 teaspoon vanilla extract

Preheat oven to 350° F. Make sure everything is at room temperature!
In an 9-inch cast-iron skillet, cook 4 tablespoons butter and brown sugar over medium heat, stirring occasionally until mixture starts to bubble and is fragrant. This doesn't take long. Turn off heat and let skillet cool down.
In a separate saucepan, cook the cranberries and apple cider until the cranberries just start to pop for about 5 minutes. You will notice the skin of the cranberries splitting and the insides literally popping out. Pour the mixture over the cooled caramel.
In a mixing bowl add the flour, baking powder, and salt and whisk to combine.
In a bowl, beat the remaining 8 tablespoons butter and brown sugar until light and fluffy. Beat in the two egg yolks, one at a time. Stir in vanilla extract. When mixed well. add the flour mixture alternately with the almond milk, starting and ending with one third of the flour. Stir just until no streaks of flour can be seen. In a separate bowl, beat the egg whites until they hold soft peaks. Fold one third of the egg whites into the batter with a rubber spatula, and then gently fold in the rest.
Pour the batter over the cranberries in the pan. Bake for 35-40 minutes or until the top is really golden brown and the cake pulls away from the sides of the pan. You want a toothpick to be able to be removed from the center cleanly. Remove from the oven and allow the cake to cool for 15 minutes. Run a knife around the edge of the pan and invert the cake onto a serving plate.
This cake is great served by itself.